1. Field of the Invention
This invention relates to a vehicle suspension system.
2. Description of the Prior Art
As disclosed, for instance, in Japanese Utility Model Publication No. 62(1987)-11203, there has been known a vehicle suspension system which has a suspension arm the inner end portion of which is bifurcated and comprises a front branch arm and a rear branch arm, and in which the inner ends of the branch arms are supported on the chassis so that the suspension arm can be displaced in the longitudinal direction of the vehicle body. The forward displacement of each branch arm is limited by a rubber bushing and forward load acting on the inner end of the suspension arm when the brake is applied is resiliently absorbed by the rubber bushing.
When a vehicle passes a gap, rearward load acts on the inner end of the suspension arm. In order to improve the driving comfort, it is preferred that the rearward load be resiliently absorbed. However, it is difficult to absorb the rearward load by a rubber bushing since the rubber bushing is hard to set to have a predetermined spring constant and the spring constant of the rubber bushing is apt to change with age. Further, it is difficult to ensure a sufficient displacement of the inner end of the suspension arm with the rubber bushing.